Usually one can run a P&L by Class to find any unassigned or not specified class entries and (usually) click on the transaction(s) and edit or add the class. But QBO and Online Payroll which is not even integrated into QBO but just a side by side are animals all their own and never act like the desktop versions. The other thing that comes into play is that if you use full service payroll you cannot edit any submitted info yourself and assisted only a month back.
I generally dismiss journal entries as a way for others to correct classifications but I do it all the time. One example is monthly insurance payments for my multiple properties. All year long they post to Unassigned or "not assigned" and once a year I craft a journal entry that credits unassigned and/or not assigned insurance expense and split assigns the same to 20-30 unit classes. I find this much easier than trying to divide a $237 payment 30 ways each month.
This might work for you to create a journal entry, credit the expenses with no class as no class and debit same expense with proper class. Do one and see if your report looks better and if so do the rest